What details should be added:
Expand the documentation to answer questions like:
What happens if more that one case evaluates to "true"? The example implies that only one case should be true, but being explicit about that would be ideal.
What is the purpose, or constraints, on "when"? Why are there both "when" and "if"?
Is "default" required? What happens if it is missing?
Article and section: https://www.elastic.co/guide/en/kibana/master/canvas-function-reference.html#case_fn
What details should be added: Expand the documentation to answer questions like: